On the Job

Roof-Pitch Jig

I built this jig about 10 years ago while waiting on a job site
for a building inspector. The parts — laminate countertop
scrap and an old 2-foot wooden level kicking around the back of
my truck — were cheap.

After cutting the countertop roughly to size, I drew a baseline
along the bottom edge and marked a pivot point at one end. Then
I measured over 24 inches and made a second mark, drew a second
line perpendicular to the baseline, and marked this line every
2 inches.

Since the run is 24 inches instead of 12 inches (to give the
jig more accuracy), each mark corresponded to a whole-number
change in pitch (2-inch rise/24-inch run = 1-in-12
pitch).

Next, I drilled holes and bolted the level to the countertop
through the pivot point. To read the pitch using the top of the
level, I had to shift the position of the pitch marks upward on
the jig. I did this by marking the free end of the level to
correspond with the position of the pivot point; then I aligned
this point with each of the marks of my original pitch layout
as I marked the new pitch lines with a felt-tipped pen, using
the top edge of the level as a guide (see illustration).

After the ink dried, I erased the pencil lines of the original
layout, then sprayed the countertop surface with clear lacquer
to preserve my final marks.

By trimming the countertop along the arc scribed by the level,
I made the jig a little more compact; I also cut a handle into
it so it would be easier to carry up to a roof.

To use the pitch finder, I rotate the level until it reads
level, then clamp it in place with a spring clamp. I usually
take three or four readings on different parts of the roof,
using the average result to ensure that a local dip or bulge
doesn't give a false reading.

Over the decade-plus that I've used this site-built tool, it
has proven to be very handy and accurate.

John Carroll is a
builder in Durham, N.C., and the author of Measuring, Marking
& Layout.

Lumber-Hanging Trick

If you gang-cut rafters, or even if you cut them one at a
time, sooner or later all those parts have to be hauled up to
the roof and installed. Framers Will Holladay and Nick Ridge
used an efficient method for making this happen on a site in
Oakland, Calif.

Will's job was to precut the entire roof on the ground, while
Nick and his crew nailed the pieces up. As Will cut the pieces
— blocks [1] and rafters [2] are shown here — he
hung them with nails along the plates or girders where they
were being installed.

This makes for very efficient framing as long as all the parts
are there. Because they're hanging exactly where they go, the
roof cutter can tell at a glance if he's missed any pieces
simply by looking at what's hanging from the wall. The
carpenters assembling the roof just reach down from the plates
and grab the next piece they need.

The method doesn't work for hanging long rafters, but you can
still hang the blocks and stack the rafters near at hand [3].
— David Frane

Skyhooked

Faced with the prospect of backing down a twisting,
half-mile-long mountainside driveway, the driver of this
40-foot flatbed tractor-trailer was looking for a place to turn
around. The crane operator, who had just hoisted into position
the truck's load of precast concrete planks, volunteered to
hook up and help out.

With the back wheels of the flatbed trailer lifted several
inches off the ground [1] and the crane operator deftly
maneuvering the trailer into position, the truck driver easily
negotiated the tight corner around the edge of the foundation
into the turnaround [2]. Then, as the truck pulled out of the
turnaround, the crane lifted the back wheels again, swinging
the trailer over several feet to clear a pile of boulders and
point the rig on its way [3].

Total elapsed time: about five minutes, which considerably sped
the arrival of the next truck waiting at the bottom of the hill
with another load of concrete planks. — Andrew
Wormer